Well I pulled the trigger and ordered the 80ohm DT 770 Pro's.
Comfort wise they appeal to me the most, I was still debating the HD 598's but decided to go with the DT's instead.
I still have yet to decide on soundcard vs Ext USB DAC/Amp. I think I am going to just try them with my onboard realtek HD and see what happens first. I still would appreciate advice on the best (for the money, I am not spending $200) sound card to power these.
Again keep in mind that these will be used 95+% of the time for gaming and I don't care about dolby/eax/5.1/etc... I am just looking for power/clarity for these headphones for gaming.
You don't have to get a soundcard if you don't need one. Onboard audio can be excellent and without background noise or hisses. It's not even rare anymore.
If you want an internal soundcard, Asus Xonar ones are excellent and not overpriced (the DG for example does the job just fine and is cheap)